Fan structure and impeller thereof

ABSTRACT

A fan structure at least includes a cap, an impeller, a bearing and a fixing shaft, wherein the cap comprises a bottom portion, a body and an accommodating space. The impeller comprises a hub and a coupling base having a ring wall and an accommodating slot. The bearing couples to the accommodating slot, and the fixing shaft penetrates through an axial hole of the bearing. The ring wall of the coupling base comprises at least one guidance hole exposing the fixing shaft. The guidance hole is in communication with the accommodating space and the accommodating slot. The lubricants can be collected inside the accommodating space of the cap through the guidance of the guidance hole to prevent the lubricants from leakage when the impeller is in rotation.

FIELD OF THE INVENTION

The present invention is generally related to a fan structure, which particularly relates to the fan structure with a guidance passage utilized for guiding lubricants back to a bearing.

BACKGROUND OF THE INVENTION

With reference to FIG. 13, a conventional fan structure 10 includes a bottom board 11, a cap 12 disposed at the bottom board 11, a stator 13, a bearing 14, a shaft 15, a hub 16 and a plurality of blades 17, wherein the stator 13 is coupled to the cap 12 for driving the shaft 15, the hub 16 and the blades 17 into rotation. However, when the shaft 15 is in rotation, lubricants utilized for lubricating the bearing 14 and the shaft 15 splash from the cap 12 through centrifugal force to lead loss of lubricants. Therefore, the friction between the shaft 15 and the bearing 14 increases so as to lower the lifetime of the fan structure 10.

SUMMARY

The primary object of the present invention is to provide a fan structure, wherein lubricants can be collected inside an accommodating space of a cap through a guidance hole of an impeller for preventing lubricants from leakage when the impeller is in rotation.

A fan structure in the present invention includes a cap, an impeller, a bearing and a fixing shaft, wherein the cap comprises a body and an accommodating space surrounded by the body. The impeller comprises a hub and a coupling base having a ring wall coupled to the hub and an accommodating slot surrounded by the ring wall, wherein the ring wall comprises at least one guidance hole communicated with the accommodating space of the cap and the accommodating slot of the coupling base. The bearing is coupled to the accommodating slot of the coupling base and comprises an axial hole. The fixing shaft penetrates the axial hole and is revealed by the guidance hole of the ring wall. When the impeller is in rotation, lubricants flow upwardly along the ring wall of the coupling base or the fixing shaft. Through effect of centrifugal force, lubricants can be collected inside the accommodating space of the cap by passing through the guidance hole of the ring wall so as to prevent lubricants from splashing and leakage when the impeller is in rotation.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective exploded view illustrating a fan structure in accordance with a first embodiment of the present invention.

FIG. 2 is a section view illustrating a fan structure in accordance with a first embodiment of the present invention.

FIG. 3 is a perspective bottom view illustrating an impeller in accordance with a first embodiment of the present invention.

FIG. 4 is a perspective diagram illustrating a bearing in accordance with a first embodiment of the present invention.

FIG. 5 is a section view illustrating a fan structure in accordance with a second embodiment of the present invention.

FIG. 6 is a perspective top view illustrating an impeller in accordance with a second embodiment of the present invention.

FIG. 7 is a perspective bottom view illustrating an impeller in accordance with a second embodiment of the present invention.

FIG. 8 is a section view illustrating a fan structure in accordance with a third embodiment of the present invention.

FIG. 9 is a perspective bottom view illustrating an impeller in accordance with a third embodiment of the present invention.

FIG. 10 is a section view illustrating a fan structure in accordance with a fourth embodiment of the present invention.

FIG. 11 is a perspective diagram illustrating a bearing in accordance with a fourth embodiment of the present invention.

FIG. 12 is a section view illustrating a fan structure in accordance with a fifth embodiment of the present invention.

FIG. 13 is a section view of a conventional fan structure.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 1, a fan structure 100 in accordance with a first embodiment of the present invention includes a cap 110, an impeller 120, a bearing 130, a fixing shaft 140, a stator 150, a circuit board 160 and a base 170, wherein the cap 110 is disposed at the base 170. The stator 150 and the circuit board 160 are attached to the cap 110 for driving the impeller 120 into rotation.

Referring to FIG. 2, the cap 110 comprises a body 111, an accommodating space 112 and a bottom portion 113, wherein the body 111 is coupled to the bottom portion 113, and the accommodating space 112 is surrounded by the body 111. With reference to FIGS. 1, 2 and 3, the impeller 120 comprises a hub 121, a plurality of blades 122 coupled to the hub 121 and a coupling base 123 having a ring wall 124 coupled to the hub 121 and an accommodating slot 125 surrounded by the ring wall 124. The ring wall 124 comprises an inner surface 124 a, an outer surface 124 b, a top surface 126, a bottom surface 127 and at least one guidance hole 128 located between the top surface 126 and the bottom surface 127. The guidance hole 128 is in communication with the inner surface 124 a and the outer surface 124 b.

With reference to FIG. 2 again, the ring wall 124 of the coupling base 123 is accommodated within the accommodating space 112 of the cap 110, and the guidance hole 128 is in communication with the accommodating space 112 and the accommodating slot 125. In this embodiment, the guidance hole 128 is recessed to the bottom surface 127 of the ring wall 124 and comprises an upper surface 128 a. The bearing 130 couples to the accommodating slot 125 of the coupling base 123. The bearing 130 is located at the accommodating space 112 of the cap 110 and comprises an axial hole 131. The fixing shaft 140 penetrates through the axial hole 131, and the guidance hole 128 of the ring wall 124 reveals the fixing shaft 140. The fixing shaft 140 comprises a first end 141 fixedly coupled to the bottom portion 113 of the cap 110 and a second end 142 protruded to the top surface 126 of the coupling base 123 through a penetration hole 123 a of the coupling base 123. Besides, the fixing shaft 140 is not in contact with the coupling base 123 to avoid any friction occurred between the fixing shaft 140 and the impeller 120 so that the rotation of the impeller 120 will not be affected. Further, the second end 142 of the fixing shaft 140 protrudes to the top surface 126 of the coupling base 123. When the fan structure 100 is installed within electronic goods, the projecting second end 142 prevents the fan structure 100 compressed by a deformed case, a deformed keyboard or an external force from abnormal operation or destruction.

With reference to FIGS. 2 and 4, in this embodiment, the bearing 130 comprises a penetration hole 132 communicated with the guidance hole 128 of the ring wall 124 and the axial hole 131, and the penetration hole 132 reveals the fixing shaft 140. In this embodiment, the fan structure 100 further includes a guidance passage W composed of the penetration hole 132 of the bearing 130 and the guidance hole 128 of the ring wall 124.

With reference to FIG. 2 again, the body 111 of the cap 110 comprises a top edge 114, and the upper surface 128 a of the guidance hole 128 is lower than the top edge 114. When the impeller 120 is driven to rotate by the stator 150, lubricants that is inside the bearing 130 flow upwardly along the fixing shaft 140 or the ring wall 124 of the coupling base 123. Through effect of centrifugal force, the flowing path of lubricants can be changed through the penetration hole 132 of the bearing 130 and the guidance hole 128 of the ring wall 124, which prevents lubricants from lastingly flowing up along the fixing shaft 140 or the ring wall 124 of the coupling base 123. Therefore, lubricants can be collected inside the accommodating space 112 of the cap 110 by passing through the guidance passage W so as to prevent lubricants leaked from the penetration hole 123 a of the coupling base 123 to the hub 121 and the top surface 126 of the coupling base 123. In addition, the upper surface 128 a of the guidance hole 128 is lower than the top edge 114 of the body 111, which prevents lubricants from splashing to the outside of the cap 110 to avoid leakage or to avoid the stator 150 from being polluted.

A second embodiment of the present invention is illustrated in FIGS. 5, 6 and 7, the primary difference between the second embodiment and the first embodiment is that the guidance hole 128 is recessed to the top surface 126 of the ring wall 124, and the guidance hole 128 comprises a lower surface 128 b lower than the top edge 114 of the body 111. With reference to FIG. 5 again, when the impeller 120 is driven to rotate by the stator 150, the lower surface 128 b of the guidance hole 128 lower than the top edge 114 of the body 111 prevents lubricants from splashing from the cap 110 through centrifugal force to avoid loss of lubricants.

A third embodiment of the present invention is illustrated in FIGS. 8 and 9, the primary difference between the third embodiment, the first embodiment and the second embodiment is that the guidance hole 128 only communicates with the inner surface 124 a and the outer surface 124 b, and the guidance hole 128 is not recessed to the top surface 126 and the bottom surface 127. In this embodiment, the upper surface 128 a and the lower surface 128 b of the guidance hole 128 are both lower than the top edge 114 of the body 111. With reference to FIG. 8, when the impeller 120 is driven to rotate by the stator 150, the upper surface 128 a and the lower surface 128 b of the guidance hole 128 are both lower than the top edge 114 of the body 111 prevent lubricants from splashing from the cap 110 through centrifugal force to avoid loss of lubricants.

A fourth embodiment of the present invention is illustrated in FIGS. 10 and 11, the primary difference between the fourth embodiment and the first embodiment is that the bearing 130 further comprises an outer ring surface 133 formed in a ladder shape, the outer ring surface 133 includes a first surface 133 a and a second surface 133 b, and the first surface 133 a is spaced apart from the ring wall 124 to define an oil storage space S communicated with the penetration hole 132 of the bearing 130 and the guidance hole 128 of the ring wall 124. The outer diameter of the first surface 133 a is smaller than that of the second surface 133b.

A fifth embodiment of the present invention is illustrated in FIG. 12. The primary difference between the fifth embodiment and the first embodiment is described as below, the bearing 130 in the fifth embodiment does not possess the penetration hole 132 in the first embodiment, the bearing 130 in the fifth embodiment does not block up the guidance hole 128 of the ring wall 124, and the guidance passage W in the fifth embodiment is the guidance hole 128 of the ring wall 124. The guidance hole 128 still reveals the fixing shaft 140 in the fifth embodiment. When the impeller 120 is driven to rotate by the stator 150, lubricants that is inside the bearing 130 flow upwardly along the fixing shaft 140 or the ring wall 124 of the coupling base 123. Through effect of centrifugal force, the flowing path of lubricants can be changed by the guidance hole 128 of the ring wall 124 to prevent lubricants from lastingly flowing up along the fixing shaft 140 or the ring wall 124 of the coupling base 123. Therefore, lubricants can be collected inside the accommodating space 112 of the cap 110 by passing through the guidance hole 128 of the ring wall 124.

In each embodiment of the present invention, the flowing path of lubricants can be changed through the guidance hole 128 of the ring wall 124 via centrifugal force, thereafter, lubricants can be collected inside the accommodating space 112 of the cap 110 by passing through the guidance hole 128, which prevents lubricants from splashing from the coupling base 123, the hub 121 or the cap 110 to avoid loss of lubricants. Furthermore, the lubricants gathered inside the accommodating space 112 of the cap 110 can repeatedly lubricate the bearing 130 so that a lubricant reclamation function can be achieved.

While this invention has been particularly illustrated and described in detail with respect to the preferred embodiments thereof, it will be clearly understood by those skilled in the art that it is not limited to the specific features and describes and various modifications and changes in form and details may be made without departing from the spirit and scope of this invention. 

What is claimed is:
 1. A fan structure including: a cap having a body and an accommodating space surrounded by the body; an impeller having a hub and a coupling base, the coupling base comprises a ring wall coupled to the hub and an accommodating slot surrounded by the ring wall, wherein the ring wall accommodated within the accommodating space of the cap comprises at least one guidance hole communicated with the accommodating space of the cap and the accommodating slot of the coupling base; a bearing coupled to the accommodating slot of the coupling base and having an axial hole; and a fixing shaft penetrating the axial hole, wherein the guidance hole of the ring wall reveals the fixing shaft.
 2. The fan structure in accordance with claim 1, wherein the ring wall comprises a top surface and a bottom surface, and the guidance hole is located between the top surface and the bottom surface.
 3. The fan structure in accordance with claim 2, wherein the guidance hole is recessed to the bottom surface.
 4. The fan structure in accordance with claim 2, wherein the guidance hole is recessed to the top surface.
 5. The fan structure in accordance with claim 1, wherein the bearing comprises a penetration hole communicated with the guidance hole of the ring wall and the axial hole, and the fixing shaft is revealed by the penetration hole.
 6. The fan structure in accordance with claim 5 further includes a guidance passage composed of the penetration hole of the bearing and the guidance hole of the ring wall.
 7. The fan structure in accordance with claim 5, wherein the bearing further comprises an outer ring surface formed in a ladder shape, the outer ring surface comprises a first surface and a second surface, and the first surface is spaced apart from the ring wall to define an oil storage space communicated with the penetration hole of the bearing and the guidance hole of the ring wall.
 8. The fan structure in accordance with claim 3, wherein the body of the cap comprises a top edge, and the guidance hole of the ring wall comprises an upper surface lower than the top edge.
 9. The fan structure in accordance with claim 4, wherein the body of the cap comprises a top edge, and the guidance hole of the ring wall comprises an lower surface lower than the top edge.
 10. An impeller of a fan structure including: a hub; and a coupling base having a ring wall coupled to the hub and an accommodating slot surrounded by the ring wall, wherein the ring wall comprises an inner surface, an outer surface and at least one guidance hole communicated with the inner surface and the outer surface.
 11. The impeller of a fan structure in accordance with claim 10, wherein the ring wall comprises a top surface and a bottom surface, and the guidance hole is located between the top surface and the bottom surface.
 12. The impeller of a fan structure in accordance with claim 11, wherein the guidance hole is recessed to the bottom surface.
 13. The impeller of a fan structure in accordance with claim 11, wherein the guidance hole is recessed to the top surface.
 14. A fan structure including: an impeller having a hub and a coupling base, the coupling base comprises a ring wall coupled to the hub and an accommodating slot surrounded by the ring wall, wherein the ring wall comprises an inner surface, an outer surface and at least one guidance hole communicated with the inner surface and the outer surface; a bearing coupled to the accommodating slot of the coupling base and having an axial hole; and a fixing shaft penetrating the axial hole, the fixing shaft is revealed by the guidance hole of the ring wall.
 15. The fan structure in accordance with claim 14, wherein the ring wall comprises a top surface and a bottom surface, and the guidance hole is located between the top surface and the bottom surface.
 16. The fan structure in accordance with claim 15, wherein the guidance hole is recessed to the bottom surface.
 17. The fan structure in accordance with claim 15, wherein the guidance hole is recessed to the top surface.
 18. The fan structure in accordance with claim 14, wherein the bearing comprises a penetration hole communicated with the guidance hole of the ring wall and the axial hole, and the fixing shaft is revealed by the penetration hole.
 19. The fan structure in accordance with claim 18 further includes a guidance passage composed of the penetration hole of the bearing and the guidance hole of the ring wall.
 20. The fan structure in accordance with claim 18, wherein the bearing further comprises an outer ring surface formed in a ladder shape, the outer ring surface includes a first surface and a second surface, and the first surface is spaced apart from the ring wall to define an oil storage space communicated with the penetration hole of the bearing and the guidance hole of the ring wall. 